Yarn winding mechanism

ABSTRACT

In a yarn winding mechanism wherein a length of yarn is wound onto a rotating bobbin, a yarn guide comprising a body supported for movement back and forth along a reciprocal path. A cam follower is affixed to a shaft which is rotatably supported by a metal sleeve positioned in an opening in the body, and the cam follower is adapted to move in a cam comprising a cylinder having a groove which is configured to permit the body to move along the reciprocal path. A yarn guide member is attached to the body for constraining the yarn to properly guide the yarn onto the bobbin. The body, cam follower, and shaft are made of a molded plastic of sufficiently high impact strength to withstand the forces applied to the guide to prevent deformation and breaking thereof and of a sufficiently low coefficient of friction to permit the body to move along the reciprocal path at the required operating speeds. The cam follower and shaft have a reinforcing member embedded therein which provides sufficient flexural rigidity to substantially prevent bending deforming, and breaking of the cam follower and shaft.

United States Patent 51 3,706,420 Lapidas et al. 1 Dec. 19, 1972 [54] YARN WINDING MECHANISM 57 ABSTRACT Filed:

Inventors: Manuel Lapidas, 47 Windmill Drive,

Sudbury;

John C. Maull, Rock Meadow Road, Uxbridge, both of Mass.

Nov. 23, 1970 Appl. No.: 92,062

U.S. Cl. ..242/43, 74/57, 74/569,

'Int. Cl. ..B65h 54/30 Field of Search ..242/43, 157 R, 158.3, 158.5;

References Cited UNITED STATES PATENTS Primary ExaminerStanley N. Gilreath Att0rney--Schiller & Pandiscio In a yarn winding mechanism wherein a length of yarn is wound onto a rotating bobbin, a yarn guide com prising a body supported for movement back and forth along a reciprocal path. A cam follower is affixed to a shaft which is rotatably supported by a metal sleeve positioned in an opening in the body, and the cam follower is adapted to move in a cam comprising a cylinder having a groove which is configured to permit the body to move along the reciprocal path. A yarn guide member is attached to the body for constraining the yarn to properly guide the yarn onto the bobbin. The body, cam follower, and shaft are made of a molded plastic of sufficiently high impact strength to withstand the forces applied to the guide to prevent deformation and breaking thereof and of a sufficiently low coefficient of friction to permit the body to move along the reciprocal path at the required operating speeds. The cam follower and shaft have a reinforcing member embedded therein which provides sufficient flexural rigidity to substantially prevent bending deforming, and breaking of the cam follower and shaft.

6 Claims, 2 Drawing Figures PATENTED 19 I972 3. 706, 420

FIG. 2.

MANUEL LAP/0,45 JOH/V c. MAULL TTORNEYS.

YARN WINDING MECHANISM This invention relates to yarn winding mechanisms and more particularly to a new and improved yarn guide for use in yarn winding mechanisms.

Most prior art yarn guides are devices which are made of metal, usually with a carbide slot for the yarn, and are operated by a helical cam or other type of reciprocating mechanism for moving the guide back and forth while a length of yarn is wound onto a bobbin. These metal yarn guides are configured very similarly to the yarn guide of the present invention, but these prior art metal guides suffer from a number of disadvantages. To obtain relatively high winding speeds, the yarn guide must be capable of reciprocating at a fairly high speed. Being made of metal, these guides must be carefully machined to close tolerances and, therefore, are relatively expensive. Further being made of metal which has a relatively high coefficient of friction and being subjected to relatively high velocity, these guides tend to wear out and require replacement quite frequently. Also, being made of a metal, these guides are relatively heavy and have a relatively high inertia to overcome whenever the end of its reciprocal path is reached. Because of their weight, the prior art guides are subjected to substantial forces each time the guide reaches the end of its reciprocal path and reverse direction. Lastly, heavy metal guides, in operation, tend to be quite noisy.

Therefore, an object of the present invention is to provide a new and improved yarn guide for use in yarn winding mechanisms.

Another object of the present invention is to provide a yarn guide which is inexpensive and simple to manufacture.

Still another object of the present invention is to provide a yarn guide which is made of amaterial having a relatively low coefficient of friction.

Yet another object of the present invention is to provide a yarn guide which is much longer wearing and requires much less frequent replacement than metal yarn guides of the prior art.

A further object of the present invention is to provide a yarn guide which is much lighter in weight than most metal guides and yet has the required rigidity and impact strength to withstand the impact shocks at turnaround.

Still a further object of the present invention is to provide a yarn guide which is capable of being reciprocated at higher velocities than prior art guides and with less inertia each time the guide reaches the end of its reciprocal path and reverses direction, and is much quieter in operation.

The above objects, advantages, and features as well as others of the present invention are accomplished by providing in a yarn winding mechanism wherein a length of yarn is wound onto a rotating bobbin, a yarn guide comprising a body slidingly supported by a pair of spaced parallel support bars for movement back and forth along a reciprocal path, a cam follower affixed to a shaft, the shaft being rotatably supported by the body, the cam followerbeing adapted for movement in a cam comprising a groove configured such as to permit the body to move along the reciprocal path, and a yarn guide member attached to the body for constraining the length of yarn to properly guide the yarn onto the bobbin, wherein the improvement comprises: the body being made of a plastic material of sufficiently high impact strength to withstand the forces applied to the guide to prevent deformation and breaking thereof and of a sufficiently low coefficient of friction to permit the body to move along the reciprocal path at the required operating speed; the cam follower and the shaft being made of the plastic; a metal sleeve positioned in an opening in the body, the sleeve rotatably supporting at least a portion of the shaft to substantially prevent deformation of the opening and the body and to substantially reduce wear due to rotation of the shaft; and a reinforcing member embedded in the cam follower and the shaft, the member substantially conforming to the general configuration of the cam follower and the shaft, the reinforcing member providing sufficient flexural rigidity to substantially prevent bending, deforming, and breaking of the cam follower and the shaft.

Other objects of the invention will in part be obvious and will in part appear hereinafter. The invention accordingly comprises the apparatus possessing the construction, combination of elements, and arrangement of parts which are exemplified in the following detailed disclosure and the scope of the application of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the present invention reference should be had to the following detailed description taken in connection with the accompanying drawings wherein:

FIG. 1 is an isometric view of the yarn guide of the present invention employed in a portion of a yarn winding mechanism; and

FIG. 2 is an isometric view of the yarn guide of the present invention.

' Referring now to the drawings, FIG. 1 shows a portion of a yarn winding mechanism for winding a yarn filament or thread 12 around a rotating bobbin shown partially at 14. The yarn winding mechanism includes a cam 16 mounted for rotation about a shaft 18. Cam 16 comprises a cylinder having a continuous closed helical groove 19 formed in the outer surface thereof which extendsentirely around the periphery of cam 16. .A yarn guide is intended to be cammed back and forth by groove 19 while supported on shaft 20 and support bar 21 both of which are parallel to one another. When cam 16 rotates, a cam follower or dog in helical groove 19 if constrained to motion along the cylindrical axis, will move in a complete degenerate ellipse which forms a linear or straight line reciprocal path along a line parallel to the axis of shaft 18. The system thus described is well known in the art.

Shown in FIGS. 1 and 2 is a yarn guide according to the present invention shown generally at 22. Yarn guide 22 includes a body in the form of a substantially hollow, cylindrical elongated sleeve 24 for mounting on shaft 20 so as to be reciprocable back and forth along the direction of double headed arrow 28. Extending radially outwardly from the outer surface of sleeve 24 is an arm 30 which has an end portion 32. End portion 32 is disposed at an obtuse angle a from arm 30. Affixed to end portion 32 is a yarn guide member 34 which is disposed substantially perpendicular to end portion 32. Member 34 has a slot 36 which extends substantially perpendicular to the axis of shaft 26. Thread 12 which is being wound onto bobbin 14 passes through slot 36 which is intended to confine thread 12 both vertically and laterally along the direction of arrow 28 so that the thread may be properly wound onto the bobbin l4.

Projecting radially outwardly from and affixed to the surface of sleeve'24 is a projection or jaw 38 having slot or groove 40 therein. .law 38 is disposed at an obtuse angle B'from arm 30. Groove 40 is intended to embrace and ride upon support bar 21. Shaft 20 and bar 21 not only provide sliding support for the yarn guide, but serve to constrain motion of the latter to a path parallel the axis of cylindrical cam 16.

Rotatably supported by jaw 38 and forming a part of yarn guide 22 is a cam follower-or dog 44. Cam follower 44 partially rests in groove 19 in cam 16. As cam 16 rotates, cam follower 44 follows along the path defined by groove 19 thereby causing yarn guide 22 to reciprocate back and forth. As bobbin 14 rotates, continuous thread 12, which passes through slot 36, is confined in slot 36 so as to eliminate undesirable vertical and lateral movement and is wound in the proper manner onto the bobbin.

' FIG. 2 shows the details'and operative relationship'of the components making up yarn guide 22. Jaw 38 has an opening or hole 46 passing completely therethrough and has a length which extends from a lower surface 48 of jaw 38 to an upper surface 50 thereof. Hole 46 is positioned such that it is substantially perpendicular with respect to the elongated dimension of sleeve 24. Hole 46 is circular in cross section. Embedded in jaw 38 is a sleeve 52 which has an opening passing completely therethrough. The opening in sleeve 52 is coextensive with opening 46. Sleeve 52 is of a length less than the total length of hole 46.

Cam follower 44 is a curved member having upper and lower surfaces 53 and 54 respectively and wedgeshaped ends 55 and 56, which define edges 58 and 60 respectively. The curvature of cam follower 44 is such that wedge-shaped ends 55 and 56 extend in a direction away from sleeve 24. Affixed to cam follower 44 in the middle of an upper surface 53 thereof is a cylindrical shaft 62. Embedded inside cam follower 44 and shaft 62 is'a specially configured reinforcing member 64. Member 64 has a special configuration which is substantially cruciform and conforms generally to the shape of cam follower 44 and shaft 62. Member 64 includes a substantially straight leg 66 which. extends from lower surface 54 of cam follower 44 through shaft 62 to the end thereof. Member 64includes another substantially straight leg 68 which is substantially perpendicular to leg 66 and is embedded in cam follower 44. Member 64 is intended to provide cam follower 44 and shaft 62 with the required flexural rigidity as will be explained. The length of shaft 62 is substantially the same as the length of hole 46 and shaft 62 is rotatably positioned inside hole 46. The outer diameter of shaft 62 is slightly less than the diameter of the circular cross section of hole 46 so that hole 46 provides adequate support for shaft 62 while at the same time permitting rotational movement of the shaft.

Yarn guide 22 is very simpleand inexpensive to manufacture. Yarn guide 22 is a composite member made of a high impact strength, low coefiicient of friction, plastic with specially configured metal reinforcing members embedded in the plastic. This composite member has all the advantages with respect to strength and rigidity as the prior art metal yarn guides without any of the disadvantages of an all metal guide. In addition, it has the additional advantages of providing a lighter weight unit having a longer life and greater wear resistance and capable of operating at higher speeds than metal guides. Except for member 34, sleeve 52, and T-shaped reinforcing member 64, yarn guide 22 is made of a molded plastic. Sleeve 24, arm 30, end portion 32 of arm 30 and jaw 38 are all integrally molded as a single piece of high impact plastic. Cam follower 44 and shaft 62 are also integrally molded as a single unit of high impact plastic. The plastic which should be used for the components of yarn guide 22 must have characteristics such that: (l) the parts are very easy to.

mold, (2) the plastic has a relatively high impact strength to withstand the forces applied to the guide when cam follower 44 and sleeve 24 reach the ends of their paths in one direction and reverse direction, .(3) the plastic has a relatively low coefficient of frictionto permit relatively high operating speeds, and (4) the plastic is relatively light weight. One plastic which may be used for the yarn guide of the present invention is Delrin plastic. Delrin is a trademark of E. I. du Pont de Nemours & Co., Inc. of Wilmington, Delaware and according to the Sixth Edition of The Condensed Chemical Dictionary published by Reinhold Publishing Corp. in 1961, Delrin is an acetal resin of composition (OCl-l derived by polymerization of formaldehyde. I

Yarn guide member 34 is made of a ceramic material which provides an extremely high resistance to wear from the yarn which passes through slot 36. A portion of member 34 rests in a groove in the upper surface of end portion 32 and is cemented in place, for example, by an epoxy. Sleeve 52 which is embedded in jaw 38 is made of metal and serves to give internal strength to hole 46 to prevent deformation thereof, as well as to provide added rigidity and strength to the entire guide 22, due to the forces applied to hole 46 by shaft 62 as cam follower 44 moves along in groove 19. Metal sleeve 52 also helps to increase the life of guide 22 by increasing the wear resistance of hole 46 as shaft 62 rotates therein. Specially configured reinforcing member'64 is made of metal and may be in the form of a metal rod or wire which is embedded in the molded plastic integral unit comprising cam follower 44 and shaft 62. Because of its special configuration and the metal material from which it is made, member 64 serves to provide plastic cam follower 44 and shaft 62 with sufficient flexural rigidity to withstand the forces applied thereto without bending, breaking, or being deformed as cam follower 44 moves along in groove 19. Because of the configuration, construction, and

materials from which yarn guide 22 is made, it is an exl060l l 0670 1. In a yarn winding mechanism for winding a length of yarn onto a rotating bobbin, said mechanism including a yarn guide comprising a body slidingly supported by a pair of spaced parallel support bars for movement back and forth along a reciprocal path, a cam follower affixed to a shaft, said shaft being rotatably supported by said body, said cam follower being adapted for movement in a cam comprising a cylinder having a groove configured such as to permit said body to move along said reciprocal path, and a yarn guide member attached to said body for constraining the length of yarn to properly guide the yarn onto said bobbin, wherein the improvement comprises:

said body being made of a synthetic polymeric plastic material of sufficiently high impact strength to withstand the forces applied to said guide to prevent deformation and breaking thereof and of a sufficiently low coefficient of friction to permit said body to move along said reciprocal path at the required operating speed;

said cam-follower and said shaft being made of said plastic;

a metal sleeve positioned in an opening in said body, said sleeve rotatably supporting at least a portion of said shaft to substantially prevent deformation of said opening and said body and to substantially reduce wear due to rotation of said shaft; and

a reinforcing member embedded in said cam follower and said shaft, said member substantially conforming to the general configuration of said cam follower and said shaft, said reinforcing member providing sufficient flexural rigidity to substantially prevent bending, deforming, and breaking of said cam follower and said shaft.

2. In a mechanism as set forth in claim 1 wherein said cam follower and shaft are integrally molded of said plastic material.

3. In a mechanism as set forth in claim 1 wherein said body includes a substantially cylindrical, elongated sleeve molded of said plastic material.

4. In a mechanism as set forth in claim 1 wherein said reinforcing member is made of metal.

5. In a mechanism as set forth in claim 1 wherein said reinforcing member is substantially cruciform.

6. In a mechanism as set forth in claim 1 wherein said yarn guide member has a slot formed therein to laterally constrain said yarn for passage therethrough, and said yarn guide member is made of a ceramic material.

l060ll 0671 

1. In a yarn winding mechanism for winding a length of yarn onto a rotating bobbin, said mechanism including a yarn guide comprising a body slidingly supported by a pair of spaced parallel support bars for movement back and forth along a reciprocal path, a cam follower affixed to a shaft, said shaft being rotatably supported by said body, said cam follower being adapted for movement in a cam comprising a cylinder having a groove configured such as to permit said body to move along said reciprocal path, and a yarn guide member attached to said body for constraining the length of yarn to properly guide the yarn onto said bobbin, wherein the improvement comprises: said body being made of a synthetic polymeric plastic materIal of sufficiently high impact strength to withstand the forces applied to said guide to prevent deformation and breaking thereof and of a sufficiently low coefficient of friction to permit said body to move along said reciprocal path at the required operating speed; said cam follower and said shaft being made of said plastic; a metal sleeve positioned in an opening in said body, said sleeve rotatably supporting at least a portion of said shaft to substantially prevent deformation of said opening and said body and to substantially reduce wear due to rotation of said shaft; and a reinforcing member embedded in said cam follower and said shaft, said member substantially conforming to the general configuration of said cam follower and said shaft, said reinforcing member providing sufficient flexural rigidity to substantially prevent bending, deforming, and breaking of said cam follower and said shaft.
 2. In a mechanism as set forth in claim 1 wherein said cam follower and shaft are integrally molded of said plastic material.
 3. In a mechanism as set forth in claim 1 wherein said body includes a substantially cylindrical, elongated sleeve molded of said plastic material.
 4. In a mechanism as set forth in claim 1 wherein said reinforcing member is made of metal.
 5. In a mechanism as set forth in claim 1 wherein said reinforcing member is substantially cruciform.
 6. In a mechanism as set forth in claim 1 wherein said yarn guide member has a slot formed therein to laterally constrain said yarn for passage therethrough, and said yarn guide member is made of a ceramic material. 